Apparatus for spinning centrifugal molds



' H. HJ'FARR APPARATUS FOR SPINNING GEN'I'RIFUGAL llQLbS Filed Dec. 1, 195a 4 Sheets-Sheet 1- I l l l I I I I I l I t l I I I ll BE T H FAR I ATTORNEY H. H. FARR ABPARATUS .FOR SPINNING CENTRIEUQML #02105 4 anti-Shut 4 Filed. D90. 1, 193av INVINEOR HEEBERT- H FHRR.

ATTORNEYS Patented Oct. 15, 1940 Herbert H. Farr, Alexander City, Ala., assignor to Form-Spun Corporation,

Alabama a corporation of Application December 1, 193 Serial No. 243,389

9 Claims,

:My invention relates to improvements in the apparatus for effecting the delivery of pipe flasks and the like onto the spinning table used in a centrifugal molding process, for the spinning and pouring of such flasks, and for the removal and delivery by their own inertia of the poured flask to the shake-out station.

In the practice of my invention, the cylindrical flasks with their rammed and dried sand lining 10 are rolled along an approach track toward the spinning table upon which they are successively received and poured while being spun, and after the metal has sufliciently solidified in a flask, it is ejected from the spinning table onto a track is along which it rolls to the station for shaking out its sand and casting preliminary to the return of the empty flask in circuit to the ramming station to receive a fresh sand lining.

It is obviously desirable that the spinning table shouldlbe of a character to permit the flasks to move in the same direction as they approach; enter, and leave the spinning table to simplify the apparatus and procedure for handling and spinning the flasks. I

It is also a matter of prime importance that simple and eflective means be provided for lowering an empty flask gently onto thespinning table so as to avoid any jarring that might injure its sand lining, and that equally simple and effective means be available for the rapid discharge from the table of the poured flask as soon as the metal therein has sufliciently solidified.

Having these objects in view, my invention contemplates the provision of aligning approach and discharge tracks with the spinning table interposed and comprising two lower sets of rollers adapted to receive and retain in position thereon the riding rings of the flask being spun, and an upper set of hold-down rollers mounted onvertically adjustable bearings adapted to be raised and lowered by a common control, conven iently accessible to the operator in charge of the pouring and handling of the flask on the table.

My invention further comprises novel mechadifierent flasks, and suitably packed to insure against access of foreign matter to their internal bearings.

My invention further contemplates the provision of a pair of cams mounted on a common 5 rocker shaft which is preferably controlled also by a lever accessible to the single spinning table operator, thecams being designed to work between the bottom sets of supporting rollers and adapted both to enable the empty flask to be eased into position on the bottom rollers and to cause the poured flask to be ejected from the table.

Another distinctive feature of my -inventio consists in the manner in which the flasks are ejected from the spinning table. The cams, acting as lifting and braking elements, throw the still rotating flask upwardly close enough to dead center position above the driven table rollers for the flask to kick itself over said rollers and thus to eject itself by its own power from the spinning table, the inertia of the rotating flask being made use of, not only to assist in ejecting it from the table, but also to run the very hot flask along the shake-out track under its own momentum and without any handling to the shake-out station.

A further ieature of my invention relates to the mounting of the levers for controlling both the hold-down rollers and the flask control cams insuch juxtaposition to the pouring spout that a single operator can, with convenience and facility, manipulate both levers, fill the spout. with molten metal, control the pouring of the flask, and clean out the spout when necessary, all without less of productive time.

My invention further comprises the novel details of construction and arrangements of parts which, in their preferred embodiment only, are illustrated in the accompanying drawings which i'orm a part of this specification, and in which: Fig. l-is a view in side elevation of the spinning table, showing the flask in spinning posi tion therein.

Fig. 2 is an enlarged end view with both levers broken away and withthe pouring spout and its support also broken away.

Fig. 3 is a cross sectional view enlarged taken on the line' IIIIH of Fig. 1, showing the ap- Fig. 4 is an enlargeddetail view in partial cross I section of one of the hold-down rollers;

in its preferred embodiment in. the drawings, in

which approach tracksii are spaced to be engaged by the cylindrical barrels or bodies of pipe flasks 6', which r011 along said tracks 5 after having a suitable sand lining jolt rammed, dried and otherwise prepared therein for the pouring opgration, which takes place upon the spinning ta le.

The spinning table comprises a suitable structural metal base 7 comprising side channels 3 having mounted crosswise at their ends the base plates 9 and i0. 011 these base plates I mount duplicate arched frames ll, carrying overhead vertical spaced guides I2. A slide block I8 is mounted between the guide members 12 at each end of the spinning frame and each block is internally bored to receive a shaft it upon which twohold-down rollers l5 are revolubly mounted. An end plate i6 is bolted to the outer end of each slide block so as to close its bore and bear against the outer faces of its respective guides l2, and the inner end of each block is flanged to overhang its respective guides on their inside edges. A top lug I! cast on which each block it is transversely bored to receive a pivot pin iii, and on the overhung ends of each pin it I mount a pair of block lifting links 19;

The links l9, at the pouring end of the spinning table, are pivotally connected by a machine'bolt 20 to the lower arm of a multiple bell crank lever 2| Journalled on a machine bolt 22 mounted in the top ends of the left 'hand guides ii. The

lifting links 19 at the right hand'end of the spinning table are similarly connected to the adjacent slide block and to a single bell crank lever 23 journalled between the upper ends of the right hand guides l2 and having its upper arm con- J nected by a bar 28 to the upper arm of the multiple bell crank lever 2|. The bar 24 has its ends bent downwardly as shown in Fig. -1'so that, when the lever arm 26, that operates the bell. crank 2!, is pulled-down to raise the hold-down rollers l5 to idle position, the intermediate portion of'the bar 24 ,will clear the lower arm of the -multiple bell crank lever 2| to which the left hand links iii are connected (see Fig. 5).

' It will also be noted, by reference to Fig. 5, that when the lever arm 25 is drawn down to lowered position to raise the hold-down rollers to idle position, both pairsof links H will be swung upwardly to the left until the notches 21 therein will ride over the top bolts 22 far enough to let the links swing past dead center position, thus locking them and the slide blocks I3, which they respectively control, msitively and securely in elevated position, which represents the idle position for the hold-down rollers IS. The connecting bar 24 causes all the links l9 to move similarly in unison, thus lifting the shaft M at both ends .equally. Enough play is allowed between the blocks l3 and their guides i 2 to allow them to fol-. low up and down freely responsive to the operation of the cranks 2i and 23 by the hand lever 28.

I mount on the inner ends of the bearing plates 9 and I0 suitable bearings for the right and left hand roller shafts 3| and 32. On these shafts in transverse alignment across the frame I mount grooved flask supporting rollers 33, which are fast on their respective shafts; the rollers at the receiving side of the table being idle rollers,

i while the rollers at the delivery side of the table are driven rollers, having their shaft 32 extended beyond the spinning table to receive a suitable driving pulley 36 by means of which they are rotated in a counter-clockwise direction as viewed in Fig. 2. The flask body has formed thereon riding rings disposed to engage the aligned sets of rollers 33 andlfi, and between these riding rings I provide a reinforcing portion to bear the shake out strap to, and near the flask center is a pair of opposed trunnions 37.

A rocker shaft ill is mounted to turn in suitable bearings ll and did on the end members of the spinning table base and it" extends centrally lengthwise of the table below the level of the rollers 33. I mount on this shaft a pair of cams or lever arms 52 disposed to engage the cylindrical barrel or body of the flask adjacent to-its riding rings 35 when raised by a lever 43, fast on the shaft at the pouringend of the spinning table so as to beconveniently accessible to a single operator who also controls the lever 26 and the pouring apparatuswhich will be later described.

In Fig. 3 a side elevation is shown of one of the v,cams Q2, and it will be noted that its underface is notched at M so as to pass over the roller shaft 3i when the cams are lowered to their normal or idle position. In such position the cams have their top edges 45 lying substantially horizontal and disposed slightly below the top level of the tracks 5, an upturned tip d6 on each cam standing slightly above the adjacent track level so as to prevent the next flask to be spun from accidently passing onto the spinning table. The top or working edge of each cam is provided with a convex portion 41 near its inner end. The whole top surface of the cam normally stands substantially below the top level of the rollers 33 and its convex portion 41 is adapted to work in the space between the right and left hand pairs of rollers 33. I provide tracks 48 on the discharge side of thetable, the tracks 5 and 48 having their ends overhanging the opposite sides of the spinning table .to such an extent and in such position that an empty flask approaching with its body riding on the falls 5 will have its riding rings 35, move without jolt into engagement with :the idler rollers 33 before the flask body leaves the tracks 5, and in like manner, the riding rings of a poured flask will remain in contact with the driving rollers 33 until the body portion of the flask has passed onto the discharge tracks 48, these transfers of flasks between track and table being accomplished in the manner hereinafter described practically without objectionable jolt or jar, particularly on the intake side where it is important to protect the sand lining of the empty flask before the pouring operation.

when the cams stand in their idle position they clear aniisk with its rings as riding the rollers 33, which latter are grooved to position the spinning flask during the pouring operation.

Molten metal, brought delivery trough 5| that is disposed concentric with the flask when the spout is mounted on its base 62 which is longitudinally slotted to receive a longitudinal rib 53 on thebottom of the spout.

from a cupola in a hand ladle, preferably in a weighed quantity, is delivered into a lined pouring spout 50, which has a- 54 at the. inner end of a guide 55 formed at the top of a bracket 53, bolted or otherwise attached to the outer end of the base plate 9. This guide 55 is provided with jam nuts 5'! which engage the outer end of the support 52 and which allow the pitch or inclination of the support to be regulated so as to govern the rate of discharge of the molten metal into the flask when the spout has been shifted forwardly to present its trough in pouring position in the adJacent open end of a flask: g 1

While the flask is being rotated it is driven at a considerable speed and it is quite important to hold it as much as possible against vibration on the spinning table rollers. 33. To this end I propose to utilize heavy hold-down rollers l5, such as are shown more in detail in Fig. 4, these rollers having a wide cylindrical tread face, considerably wider than that of the riding rings "with which they coact, so that regardless of endact yieldingly to hold the flask being spun in casting operation.

It is important to note that these large, heavy, hold-down rollers l5 allow for a suitable provision to reduce their friction and to protect their bearings, and to this end-I bore out these rollers IE to form a bearing chamber 60 in which I mount a pair of ball bearings 6|, the outer' race being held in position by a cast iron retaining ring 82, and the inner race being held in posi- 1 tion by a dove-tail joint with a self locking collar 33, a suitable set screw 63 holding each collar in position on the shaft l3, and a packing ring 55 disposed between the adjacent ring '52 and collar 63 seals the chamber at each end against the ingress of dust and dirt and against the egress of lubricant introduced-through a drilled and tapped lubricant hole 33 normally closed by a pressure grease cup 3?. The rings .62 are screwed to the sides of the rollers and engage their respective outer ball races between them and an inner shoulder provided in the chamber 50.

In operation, assuming the earns 32 lowered to idle position (Fig. 3), an empty flask with a prepared and dried sand'lining standing on tracks 5 against the stop tips 35 of the cams,

as soon as the table is ready to receive this empty flask, the table operator, standing at one end of the table, and the core setter, who has attended to the drying and setting of the cores in the approaching flask, standing at the other end of the table, grasp and push the flask over the stops it and roll it along tracks 5 until its riding rings engage the idler rollers '33, in which position the flask body stands above and clear of the cams 35 and to the left of the shaft 3i come to rest upon both sets of rollers 33 on the table. The flask throughout this introductory movement is steadied by hand by the operator and the core setter so that it can be brought into working position on the rollers quickly and yet without any jolt or jar that would tend to damage its sand lining. Thereupon the core setter returns to his task, the table operator grasps lever 26, which has been standing in its lowered position with the hold-down rollers i5 elevated, and raises this lever to throw both sets of links I9 over past dead center and lower these rollers onto the riding rings of the flask. He

.thereupon slides the pouring spout 50 forward to present its trough in pouring position in the.

flask, and having obtained a measured charge of molten metalin a hand ladle he pours'same into the pouring spout, and, preferably with his foot, throws a starter switch, not shown, to start the drive to the pulleys 34 and the right hand rollers 33. The flask, containing only a relatively small charge'of molten metal, such as would be required for the production of a soil pipe, only requires about one and a half minutes for such metal to'be uniformly distributed over the sand lining 63 of the flask and to solidify sumciently to form the pipe 69 and be ready for the flask removal operation. During this minute and a half interval the table operator is free to return his ladle to the cupola, to draw back the pouring spout and clean it and its trough if needed, and to attend to other details before cutting off the switch'and stopping the drive. When this is done, the lever 26 is grasped and pulled down to raise the hold-down rollers and lock them in elevated position. The cam lever 43 is then depressed and the cams rocked upwardly to engage the rotating flask and act as a brake thereon as well as a lifting means therefor, by which the still spinning flask is pushed up with its riding rings riding up the down-going side of the driven rollers 33 until it is raised almost to dead center position overthe right hand rollers 33, from which position it will kick itself over the top of these rollers by its own inertia and, still turning in a clockwise direction, will roll itself downwardly off said driving rollers 33 and onto the tracks 38 along which it will continue to roll under its own inertia until it reaches the shakeout station, thus avoiding the necessity of men having to handle the very hot, poured flask along this track 33.

The lever 43 is then thrown against stop 38 to restore earns 32 to initial position in which they clear shaft 3! and their tips will form stops for the next empty flask to be spun, which flask is then pushed onto the table and the process is repeated, only the time of the table operator and part of the time of the core setter being required to attend to all the duties incident to the handling and pouring of empty flasks and the delivery of the poured flasks to the shake-out station.

It will of course be understood that the table operator learns by experience the proper speed of rotation and the braking eifect of the cams which will give the poured flasks when ejected the requisite rotation to insure their delivery to the shakeout station. 3

It is not essential that the cams be used in the operation of introducing soil. pipe flasks ontothe table as the table operatorand core setter can readily handle such empty flaslm so as to. ease them into spinning position on the table rollers 33, but to speed up the operation, these cams are importantto brake the rotation of the flask after itfi'has been poured so as to slow it up quickly and discharge it while still spinning, thus obtaining in a very simple and eflective manner a rapid discharge of the poured flask and speeding up the time for operations at the spinning table.

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications, without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are imposed by the. prior art or as are specifically set forth in the appended claims.

What I claim is:

1. In combination, aspinning table for pouring centrifugal flasks, spaced rollershafts mounted on said table, rollers on said shafts, means to drive the flask engaging surfaces of the rollers on the out-going side of said table counter to the out-going direction of motion of a poured flask, a lever operated rocker shaft carrying flask ejector. arms pivoted below and disposed between said roller shafts, and means to rock said arms upwardly into position to engage the up-going side of a poured flask rotating clockwise on driven rollers moving clockwise and raise said flask into position to kick itself over said driven rollers.

2. In combination, a spinning table for cylindrical centrifugal flasks, tracks on one side of said table along which the empty flasks roll to said table, tracks leading to a shake-out station on the opposite side of said table: along which the poured flasks roll themselves away from said table, means to rotate the flasks on said table, and means to deliver the poured flasks still rotating from said table onto said latter tracks comprising angular arms with a vertical member pivoted below and between the rollers and a hori-;

drical centrifugal flasks, tracks on one side of said table along which the empty flasks roll to said table, tracks leading to a shake-out station on the opposite side of said table along which the poured flasks roll themselves away from said table, means to rotate the flasks on said table, and means to deliver the poured flasks still rotating from said table'onto said latter tracks, both said tracks being disposed adjacent to the upper level of table rollers and in position to deliver and receive flasks directly to and from said table rollers, said latter means comprising angled arms with their vertical members pivotally mounted for joint movement between the table rolls and with their tops normally projecting below the level of the table rolls towards the approaching empty flasks and having a convex eccentric surface adjacent to the junction of said arm members with an ejector extension beyond said surface, and lever means to rock said arms.

4. In a table for spinning a centrifugal molding flask, comprising lower spaced sets of rollers by which a. flask is supported and rotated in its passage across said table, hold-down rollers mounted for free downward 'movement to engage both ends of a spinning flask to hold it by gravity against displacement from its supporting rollers,

and a common means disposed above the path of the flasks and operable from one end of said table for raising and lowering said hold-down rollers in unison, said means comprising at each end of germs? the table a bell crank and link connection to ,the adjacent slide, in combination with an overhead arm connecting said cranks in position to allow themto swing their connections to said links past dead center, stops to check said cranks when past dead center, and a lever to throw said cranks.

5. In a centrifugal casting machine 'having ,flask transfer means, pivotally mounted to rock laterally between said roll assemblies and having a lateral extension disposed with its free end overhanging the receiving roll assembly while receiving an empty flask, and means to rock said transfer means and cause itslateral extension to engage and push the poured flask up and over the delivery roll assembly and deliver it onto said flask receiving means- I a 6. In a centrifugal casting machine having means to present empty flasks thereto and to receive poured flasks therefrom, a flask receiving roll assembly and a flask delivery roll assembly spaced to receive and spin a flask between them, flask transfer means pivotally mounted to rock laterally between said roll assemblies and having a lateral extension. disposed with its free end overhanging the receiving roll assembly while receiving an empty flask, means to rock said transfer means and cause its lateral extension to endelivery roll assembly and deliver it onto said flask receiving means, and means to drive said latter assembly counter to the travel of the out: going flask whereby the flask reaches the flask receiving means with a spinning motion, ,the in ertia of which runs the flask away from. said bed.

7. A centrifugal casting machine according to claim 5, in which the lateral extension has a cam portion disposed to engage the entering empty flask and ease it down into spinning position between said roll assemblies.

8. A centrifugal casting machine according to claim 5, in which the lateral extension has a cam portion disposed to work between the roll assemblies and adapted to engage the entering empty flask and ease it down into spinning position between said roll assemblies.

9. In a centrifugal casting machine interposed between a delivery track for empty flasks and a receiving track for poured'flasks, said machine comprising spaced roll assemblies arranged to receive and spin between them a flask being poured, a drive for the roll assemblies which imparts .to the assembly -rolls,on the side of the receiving track a motion overhead away from said track, a rocker shaft mounted below the position of the spinning flask, rocker arms on said shaft rising vertically between the roll assemblies, and cam ejector arms carried by said rocker arms and nor HERBERT H. FARR. 

